Slide tray



W. J. HALL Nov. 21, 1967 SLIDE TRAY 5 Sheets-Sheet 1 Original FiledMarch 1 1963 INVENTOR. Wlier JHGZZ, BY p M 6M- 1 l @f? W. J. HALL Nov.21, 1967 SLIDE TRAY 5 Sheets-Sheet 2 Original Filed March 1, 1963INYENTOR WQZ/fer J Ha ZZ, BY L M! L V C2?/9;

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' SLIDE TRAY Original Filed March 1, 1963 5 Sheets-Sheet 3 INVENTOR.

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W. J. HALL Nov. 21, 1967 SLIDE TRAY 5 Sheets-Sheet 4 Original F'iledMarch 1, 1965 INVENTOR VVQZZZfi/f/QZA 0 M g M1 W. J. HALL SLIDE TRAYNov. 21, 1967 5 Sheets-Sh 5 Original Filed March 1 1963 m m m MIHIHIHIIan hm li -4H1] INVENTOR.

United States Patent 3,353,667 SLIDE TRAY Walter J. Hall, Chicago, Ill.,assignor, by mesne assignments, to General Aniline & Film Corporation,New York, N.Y., a corporation of Delaware Original application Mar. 1,1963, Ser. No. 262,098, now Patent No. 3,209,647, dated Oct. 5, 1965.Divided and this application May 3, 1965, Ser. No. 461,574

4 Claims. (Cl. 206-73) This invention relates, generally, to innovationsand improvements in photographic slide projectors, and more particularlyto a slide projector adapted to have either a conventional, elongatedbox-like, slide magazine or tray or a circular slide tray operativelyassociated therewith. This application is a division of my applicationSer. No. 262,098, filed Mar. 1, 1963, now U.S. Patent No. 3,209,- 647,granted Oct. 5, 1965.

As it is known to those skilled in the art, photographic slide trays ormagazines are provided in two basic forms: viz., a box-like slide trayadapted to be received in a slide projector for linear slide indexingmovement, or a circular slide tray adapted to be received in a slideprojector for rotary slide indexing movement. Circular slide trays maybe of the type adapted to rotate in either a vertical or horizontalplane. Heretofore, slide projectors have been incapable of accepting andoperating with linear and/ or rotary slide trays with equal facility.

It is a primary object of this invention to provide a slide projectoradapted to have either an elongated boxlike slide tray or a circularslide tray operatively associated therewith.

It is another object of the present invention to provide in a slideprojector of the type characterized by a housing having, on the exteriorthereof, a longitudinally extending slide-tray-receiving groove orchannel, means for alternately supporting an elongated box-like slidetray and a vertically disposed circular slide tray in said groove.

A further object of the present invention is to provide in a slideprojector of the type characterized by a housing having, on the exteriorthereof, a longitudinally extending slide-tray-receiving groove, meansfor operatively supporting a circular slide tray in said groove in avertically extending position, which means include protruding meanspermanently ailixed to the projector and shaped and spaced fornon-interfering relationship with a boxlike slide tray when the latteris operatively supported in the groove.

An even further object of the present invention is to provide a new andimproved vertically extending circular slide tray adapted for operativerotation while supported at the periphery thereof and adapted to bestabilized by engagement of an annular hub track thereof with guidetrack means on a projector.

It is a still further object of the present invention to provide acircular slide tray having new and improved slide retaining means.

These and other objects and advantages of the inven tion will becomeapparent from the following specification wherein like numerals refer tosimilar parts throughout.

In the drawings:

FIG. 1 is an elevational view of a slide projector and circular slidetray illustrating this invention, with a portion of the slide tray beingbroken away for better illustration of the invention;

FIG. 2 is a rear elevational view of the and circular slide tray of FIG.1;

FIG. 3 is a top plan view of the slide projector and circular slide trayof FIG. 1;

FIG. 4 is an enlarged fragmentary section taken along the line 4-4 ofFIG. 1;

slide projector 3,353,667 Patented Nov. 21, 1967 FIG. 5 is a fragmentarysection taken along the line 5-5 of FIG. 3 with certain parts of theprojector not being shown for better illustration of the invention;

FIG. 6 is an enlarged fragmentary section taken along the line 6-6 ofFIG. 5;

FIG. 7 is an enlarged fragmentary section taken along the line 7-7 ofFIG. 1 showing the circular slide tray engaging protruding means mountedin the slide-trayreceiving groove of the projector, with certain partsof the projector not being shown;

FIG. 8a is a fragmentary plan view of one of the spring clip retainermembers of the circular slide tray of this invention, the retainer beingshown before the same is bent in arcuate form along the length thereof;

FIG. 8b is a view similar to FIG. 8a showing the other side of one ofthe spring clip retainer members;

FIG. 9 is a side elevational view of the slide projector of FIG. 1having a box-like slide tray operably associated therewith; and

FIG. 10 is a section taken along the line 10-10 of FIG. 9.

FIGS. 1 through 3 show a photographic slide projector, generallydesignated 10, which projector includes a housing or casing 11 having alongitudinally extending slidetray-receiving groove, generallydesignated 12, formed in the exterior thereof. A control panel portion13 having a number of suitable control buttons 14 and control knobs 15operably mounted thereon extends along one side of the projector. Theprojector also includes a carrying handle 18, a snap-on cover (notshown), an on-oif-lamp switch 19 (FIG. 2) and louvers 26 through whichair may be drawn for cooling the optical system of the slide projector.The casing has an electric socket 22 recessed therein adapted to receivea conventional male plug on the end of an electric cord for applyingelectric power to the slide projector. The operating components of theslide projector will not be described as they form no part of thepresent invention. *However, it will be understood that the slideprojector 10 contains suitable components including a blower, lamp,reflector, and lenses for projecting photographic slides (e.g. 35 mm.slides) through an objective lens supported in an adjustable housing 23(FIG. 3), which housing is suitably mounted for axial movement withinthe casing. By way of reference the inner mechanism of the projector maycorrespond to that shown and disclosed in Brown application, Ser. No.824,877, filed July 3, 1959, now U.S. Patent No. 3,120,150, granted Feb.4, 1964.

As best seen in FIGS. 2 and 4, the slide-tray-receiving groove 12includes a base or floor 25 and side walls 26 and 27, the latter wallcontaining an aperture 28 (FIG. 5) at the mid-point thereof. Side wall26 includes a vertically extending slide-receiving slot 29 at themidpoint thereof, which slot exposes slide receiving means in the formof parallel, horizontally extending upper and lower guide tracks 30a and3012, respectively. The guide tracks extend at right angles to thegroove 12, and the tip of upper guide track 30a extends a short distancethrough slot 29 into the groove 12. Floor 25 is provided with aplurality of parallel, spaced apart, longitudinally extending ribs 31for supporting a slide tray in groove 12; the function of ribs 31 willbe more fully explained below.

The control panel portion 13 of the slide projector includes atransversely extending recess 32 (FIG. 1) in which is slidably mounted asuitable slide carrier 33- having a handle 34 extending upwardlytherefrom. The slide carrier includes a pusher bar 35 (FIG. 4) adaptedto extend through aperture 28 in wall 27. It will be understood that theslide carrier is adapted for reciprocal movement in recess 32 forpushing photographic slides by the bar 35 from a slide tray adapted tobe received in groove 12 into slot 29 and for returning slides from theslot to the t slide tray. Flipper or kicker means (not shown) areprovided with the slide carrier for returning a slide to the slide tray.

As seen in FIG. 4, the slide-tray-receiving groove 12 includes anopening 36 in opposed alignment with the slot 29, which opening isformed at the intersection between base 25 and side wall 27. A traydriving pinion 37 operatively associated with the slide carriage 33 andadapted for rotation about a vertical axis has a toothed portion thereofextending through opening 36 and into the groove 12. As will be morefully explained below in connection with the description of the slidetrays adapted to be associated with the projector 10, the pinion 37 isadapted to index or rotate in response to movement of slide carriage 33for indexing of a slide tray received in groove 12.

The circular slide tray of this invention, generally designated 41 willbe seen from FIGS. 1 through 3 to be of the vertically disposed typeincluding inner and outer concentric walls 41 and 42, respectively,having a plurality of radially disposed circumferentially spacedpartitions or septums 43 extending therebetween. The partitions 43 areclosely spaced apart defining a plurality of radially arranged slidereceiving spaces or compartments in the circular slide tray. It will beunderstood that a conventional photographic slide (e.g. 35 mm.transparency mounted in a cardboard slide mount), fragmentarily shown byphantom lines and indicated 45 in FIG. 4, is adapted to be received ineach of the slide receiving spaces 44 for movement axially of thecircular slide tray into the slot 29 of the projector 10' when the slidetray is operatively supported within the groove 12. The circular slidetray 40 is further characterized by an annular band portion 47 and aplurality of circumferentially spaced apart axially extending ribs 48formed on the outer surface of the outer wall 42. The circular slidetray, 7

which is preferably molded from a suitable plastic material, includes anouter vertical face characterized by an outwardly extending annular hubflange 49 integral with the inner wall 41, an annular ring 50 secured toeach of the partitions 43 and an annular rack formation of teeth 51. Thecircular slide tray includes an inner face characterized by an inwardlyextending annular hub flange 52 integral with the inner wall 41.

The circular slide tray 40 is adapted to be operatively received invertically extending disposition in the longitudinally extendingslide-tray-receiving groove 12 with one of the slide-receiving spaces 44in alignment with the slide-receiving slot 29. In other words, thecircular slide tray of this invention is mounted for rotation about itsprincipal axis, i.e., its central longitudinal axis, which axis isparallel to a transverse axis extendingthrough slot 29. As best seen inFIG. 4, when the slide tray 40 is received in groove 12 one of the ribs48 of the slide tray engages the innermost n'b 31 on the base 25 of thegroove for establishing a support point between the slide tray andgroove. With the circular slide tray 40 in this dispositionin groove 12,certain teeth 51 on the slide tray are in mes-hing engagement withcertain teeth of gear 37. R- tation or indexing of gear 37- in responseto movement of slide carrier 33 indexes the circular slide tray forpositioning one of the adjacent slide receiving spaces 44 in alignmentwith slot 29, depending upon the direction the pinion gear 37 is driven.However, the circular slide tray 40- is not supported by engagement ofteeth 51- and the teeth on gear 37. In addition to the support forrthecircular slide tray established by transverse engagement of one of; theribs 48 with the innermost rib 31, further means are provided forslidably engaging the periphery of the slide tray adjacent the outerface thereof for operatively supporting the slide tray in the groove 12and preventing the same from rolling from the groove.

As seen in FIGS. 5, 6 and 7, this means is in the form of a pair of lugsor protruding inserts 55, which lugs.

4. are bolted or riveted to the side wall 27 of the slide-trayreceivinggroove 12 one on each side of the aperture 28. Each lug 55 includes acentral rounded hub portion 56 having a flattened top 57. As seen inFIGS. 5 and 7, the lugs 55 are mounted on the side wall 27 for engagingthe periphery of the circular slide tray at points on the rounded hubportions 56 just inwardly of the flat portions 57. The protrudinginserts or lugs are located on side wall 27 for slidablyengaging theperiphery of the circular slide tray when the same is operativelypositioned in groove 12 with one of the tray spaces 44 in alignment withslot 29. The circular slide tray includes an outer annular rim portion42a (FIG. 7) adapted for slidable engagement with the hub portions 56 ofthe lugs.

From the foregoing it is believed to be apparent that the circular slidetray 49 is' supported in groove 12 in vertically extending dispositionby being contacted at three points on the periphery thereof. One pointof contact is established at the periphery of the tray adjacent theinner face thereof by engagement of one of the ribs 48 with theinnermost rib 31 of the base 25. The other two points of contact at theperiphery of the tray are adjacent the outer face thereof and areestablished by contact of the annular band portion 42a with theprotruding inserts 55. The inserts or lugs 55 are spaced one forwardlyand one rearwardly of the principal axis of tray 40 for engaging theperiphery of'the tray at spaced apart points forwardly and rearwardly ofthis axis. The lugs position and support the tray for selectivealignment of spaces 44 therein with the slot 29 by engagement of theteeth on gear 37 with the teeth 51 on the tray, and the lugs alsoprevent the circular slide tray from rolling from. groove 12. It will beapparent that tray 40 is removably supported in groove 12 and adaptedfor operable rotation therein by slid ing engagement of the peripheralportions of the tray with the protruding inserts 55 and one of the ribs31. In the preferred form of the invention the slide tray ribs 48 areshown as adapted to engage only one rib 31, i.e., the innermost rib, onthe base or floor portion of the groove 12. This single point contactbetween the periphery of the tray and the groove 12 is not critical. Thecross-section of the tray 40 or groove 12 or both may be appropriatelyvaried for allowing ribs 48 to engage other of the ribs 31 in thegroove. In this case the other ribs will serve to support the tray sothat the teeth 51 thereon will be in mating alignment with the teeth ongear 37, and in this case the lugs 55 function only for aligning thespaces 44 with slot29 and for preventing the circular slide tray fromrolling in. the groove 12.

As noted in FIG. 4, the upper guide track 30a projecting throughslot 29in. the projector casing is in alignment with an annular planar surfacedefined by the outside surface of the annular inner hub flange 52 (FIG.4). During rotation of circular slide tray 40 by gear 37 annular flange52 intermittently abuts or slides against the end of upper guide track30a. Ifthe projector is tilted slightly to the side away from thecontrol panel portion 13, the flange 52 will rest continuously againstthe protruding end of the track 30a. This action serves to stabilizesupport of slide tray 4%) in groove 12.

FIGS. 9 and 10 show the slide projector 10 having a box-like slide tray,generally designated 60, operatively supported in theslide-t-ray-receiving groove 12. The slide tray 60, which may be of thetype disclosed in the Brown application, Ser. No. 824,877, filed July3,1959, includes a base portion having a floor or bottom 61 adapted forsliding engagement with the ribs 31 provided on the base 25 of thegroove 12. The slide, tray 60 further includes a cover 62v adapted to beremovably or hingedly attached to the base portion of the slide tray.The base portion of the slide tray includes end walls (not shown) and aplurality of parallel. partitions 63 evenly spaced apart between the endwalls. The partitions 63 define a plurality of slide receiving spacesfor receiving conventional photographic slides, one of which slides isshown in phantom lines and indicated 64 in FIG. 10. The cover 62includes a plurality of depending ribs 65 adapted for respectivealignment with partitions 63 for further defining the slide receivingspaces in the slide tray 60. The cover 62 also includes a plurality ofspring clips 66 attached to the underside thereof, which spring clipsare adapted to engage the upper edges of the slides for securely holdingthe same in place in the slide tray. The outer face of slide tray 60,i.e., the face adjacent groove side wall 27, includes a longitudinallyextending opening defined by upper and lower base portions 68, 69respectively. This open space on the outer face of slide tray 60 allowspusher bar 35 associated with slide carrier 33 to engage the outsideedge of one of the slides supported in the slide tray for pushing theslide into slot 29 of the slide projector housing. Lower base portion 69is provided with a rack of teeth 71 extending along the length thereof,which teeth are adapted to mesh with the teeth on driving pinion 37 forindexing of slide tray 60 by pinion 37. As it will be noted from FIG.10, the protruding inserts or lugs 55 are located on side wall 27 fornon-interfering relation with slide tray 60. More particularly, theflattened portions 57 of the lugs 55 clear the bottom of base portion 63when slide tray 60 is operatively positioned in groove 12. By thisconstruction it will be apparent that lugs 55, which are located ingroove 12 for support of the circular slide tray 40, in no way interferewith the operation of slide tray 60 when the latter is operativelyassociated with the slide projector. A number of other commerciallyavailable, linear or straight slide trays may be used in the groove 12.

It is desirable to provide the circular slide tray 40 With means forpreventing photographic slides from falling from the slide receivingspaces therein if the tray is inadvertently tipped during handling ofthe same. The circular slide tray 40 includes such means in the form ofa plurality of detachable spring clip retainers, generally designated75, which retainers are illustrated in FIGS. 7 and 8. The retainer 75 isgenerally U-shaped in crosssection and includes a first leg 76 having atleast one lug 77 extending at a right angle from one edge thereof (FIGS.8a and 8b). The other leg of retainer 75 is in the form of a pluralityof parallel, spaced-apart spring fingers 78.

(As seen in FIG. 7, outer wall 42 of the circular slide tray includesadjacent the outer face thereof an annular portion 80 of greater insidediameter than the inside diameter of the major portion of the outerwall.) This portion of the outer wall 42 is separated from the majorportion of this wall by an annular shoulder 81, which should is undercutdefining an annular lip 82. The annular portion 80 of outer wall 42includes a plurality of circumferentially spaced-apart, axiallyextending grooves 84 in the inner surface thereof. The grooves 84 openat one end thereof into teeth 51 on the outer face of the circular slidetray (FIGS. 1 and 7). The spring clip retainer 75 is adapted to bedetachably received in the circular slide tray by bending the retainerin arcuate form along the length thereof and by inserting the samebetween annular ring 50 and annular portion 80. The retainer 75 ispushed into the slide tray (to the left as seen in FIG. 7) until thebight portion of the retainer engages shoulder 81. Axially extendinggroove 84 is adapted to receive lug 77 as the spring retainer is forcedinwardly in the circular slide tray. Engagement of lug 77 in groove 84aids in detachably securing the retainer in place in the circular slidetray and prevents movement of the retainer along the length thereofrelative to the circular slide tray. A single retainer 75 of sufiicientlength may be provided for extending completely around annular portion80. In the preferred form of the invention a number of retainers 75 areprovided, which retainers are adapted to be bent in arcuate form andmounted in end-to-end relationship in annular portion 80. It Will beunderstood that the retainer or retainers are circumferentially locatedin the slide tray by engagement of lugs 77 in grooves 34 so that aspring finger 78 is in alignment with each of the slide receiving spaces44. As noted in FIG. 7, each spring 78 is adapted to engage the inneredge of one of the photographic slides 45 for holding the latter inplace in the circular slide tray. The spring fingers prevent inadvertentseparation of the slides from the circular slide tray but permit thesides to be easily pushed from the slide receiving spaces or returnedthereto by the slide carriage.

Thus it will be seen that this invention provides in a slide projectorof the type characterized by a housing having a longitudinally extendingslide-tray-receiving groove, means for alternately supporting anelongated box-like slide tray and a circular slide tray in the groove.The protruding inserts or lugs provided in the longitudinally extendinggroove in the projector for operably supporting the circular slide traytherein do not in any way interfere with the operation of a box-likeslide tray when the latter is operatively positioned in the groove. Itwill be realized that it is within the scope of this invention toprovide the protruding inserts in other forms or to provide theprotruding inserts as an integral part of the side walls defining thegroove. In the preferred form of the invention the inserts or lugs 55 aswell as the end of guide track 3% are made of a hard and smoothmaterial, such as nylon, to minimize friction between these parts andthe periphery of the tray.

It will be realized that this invention provides novel slide projectingmeans wherein a circular slide tray, elongated box-like slide tray andmeans on the projector for operatively supporting these trays may bemanufactured with ease and at a low cost. Exact tolerances need not beadhered to in the construction of the trays or in the shape of theslide-tray receiving groove in the projector as the circular slide tray49 will be operatively supported in groove 12 in vertically extendingdisposition as long as any three contact or support points areestablished between the periphery of the tray and the surface of groove12. As mentioned above, in the preferred embodiment of the invention thethree support points are defined by the two protruding inserts or lugs55 and the innermost rib 31 of base 25. However, in certain instances,e.g., if tray 46 is slightly wider than usual or if guide track 30aextends more than the usual distance into groove 12, circular slide tray40 may be operatively supported only by engagement of the peripherythereof with both lugs 55 and with the tip of upper guide track 30a. Insome instances circular slide tray 40 may be supported by engaging thetip of upper guide track 30a, the pinion gear 37 and one or both of theinserts 55. The circular slide tray is of light Weight and Symmetricalconstruction and almost any three point contact between its peripheryand groove 12 will serve to support tray 40 operatively in groove 12.

While the invention has been shown in but one form it will be obvious tothose skilled in the art that it is not to be so limited, but on thecontrary it is susceptible of various changes and modifications withoutdeparting, from the spirit and scope of the appended claims.

I claim:

1. In a circular slide tray, the construction comprising, inner andouter concentric walls having a plurality of radially disposedcircumferentially spaced partitions arranged therebetween, saidpartitions defining therebetween a plurality of axially extending slidereceiving spaces, said outer wall having a first inner face portionthereof of greater inside diameter than the inside diameter of theremaining inner face portion of the outer wall, said portions beingseparated by an annular shoulder, the edge portions of said partitionsadjacent said first inner face portion being in uniform spaced relationwith the latter 7 thereby defining an annular space, an annular planarmember extending in uniform, closed spaced relation with the edge ofsaid outer Wall adjacent said first portion thereof, said planar memberhaving an edge thereof extending in adjacent relation with the innerconfines of said annular space, annular spring clip retaining meansmounted in said annular space, said retaining means being generallyU-shaped in cross-section and having the bight portion thereof inengagement with said shoulder with one leg of the retaining means beingin substantial coextensive contact with said first inner face portionand with the other leg of said retaining means consisting of a pluralityof individual spring fingers, said spring fingers normally yieldablyengaging fixed means adjacent the inner confines of said annular spaceand being arranged in respective slide receiving spaces for resilientengagement with the edges of slides received therein.

2. The construction according to claim 1 further defined by, said outerWall having a plurality of recesses opening into said first inner faceportion thereof, said retaining means including a plurality of lugsformed on said one leg thereof, which lugs are received in respectiverecesses for aiding in securing the retaining means in said annularspace.

3. A tray for photographic slides comprising, a pair of uniformly spacedwalls having spaced partitions therebetween defining a plurality ofslide receiving spaces, said magazine having an open inner face betweensaid walls for entry of slides into said spaces and for exit of slidesthereform, said magazine having an outer face defined in part by aplanar member extending in uniform spaced relation with the adjacentedge of one of said walls thereby defining with said edge a narrow slotopening at said outer face and also opening into each of said slidereceiving spaces, a portion of said' one wall adjacent said edge thereofbeing in opposed spaced relation With corresponding edge portions ofsaid partitions thereby defining an annular space communicating withsaid slot, spring clip retainer means of generally U-shapecross-section, said retainer means being substantially containedWithinsaid annular spce with the distal end portions of the former beingdisposed adjacent said slot, which retainer means has one leg portionthereof in substantial coextensive contact withthe inside face of saidportion of said one wall and has its other leg portion in pressingengagement with fixed means adjacent the inner confines of said annularspace, said other leg portion being in the form of a plurality of springfingers one extending into each of said slide receiving spaces forretaining slides therein.

4. The tray according to claim 1 wherein said retainer means and saidone Wall have respective lugs and recesses with the former beingreceived in the latter.

References Cited UNITED STATES PATENTS 326,493 9/ 1885 Goldsmith 312-295XR 2,278,295 3/1942 Wilson 206-62 XR 2,900,074 8/ 1959 Windman 206-73'X3,045,816 7/1962 King 206-73 3,120,150 2/1964 Brown 206-62 XR 3,159,93412/1964 Wiklund 206-73 XR 3,187,890 6/1965 Brown 206-73 T HERON E.CONDON, Primary Examiner J. M. CASKIE, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION fatent No.3,353,667

November 21, 1967 Walter J. Hall corrected below.

Column 5, line 5 5, for "should" read shoulder column 7, line 30, for"thereform" read therefrom column 8, line 8 for "spce" read space line17, for the claim reference numeral "1" read 3 Signed and sealed this27th day of May 1969,

(SEAL) 2 Attest: V Edward M. Fletcher, Jr.

Attesting Officer Commissioner Patents

1. IN A CIRCULAR SLIDE TRAY, THE CONSTRUCTION COMPRISING, INNER ANDOUTER CONCENTRIC WALLS HAVING A PLURALITY OF RADIALLY DISPOSEDCIRCUMFERENTIALLY SPACED PARTITIONS ARRANGED THEREBETWEEN, SAIDPARTITIONS DEFINING THEREBETWEEN A PLURALITY OF AXIALLY EXTENDING SLIDERECEIVING SPACES, SAID OUTER WALL HAVING A FIRST INNER FACE PORTIONTHEREOF OF GREATER INSIDE DIAMETER THAN THE INSIDE DIAMETER OF THEREMAINING INNER FACE PORTION OF THE OUTER WALL, SAID PORTIONS BEINGSEPARATED BY AN ANNULAR SHOULDER, THE EDGE PORTIONS OF SAID PARTITIONSADJACENT SAID FIRST INNER FACE PORTION BEING IN UNIFORM SPACED RELATIONWITH THE LATTER THEREBY DEFINING AN ANNULAR SPACE, AN ANNULAR PLANARMEMBER EXTENDING IN UNIFORM, CLOSED SPACED RELATION WITH THE EDGE OFSAID OUTER WALL ADJACENT SAID FIRST PORTION THEREOF, SAID PLANAR MEMBERHAVING AN EDGE THEREOF EXTENDING IN ADJACENT RELATION WITH THE INNERCONFINES OF SAID ANNULAR SPACE, ANNULAR SPRING CLIP RETAINING MEANSMOUNTED IN SAID ANNULAR SPACE, SAID RETAINING MEANS BEING GENERALLYU-SHAPED IN CROSS-SECTION AND HAVING THE BIGHT PORTION THEREOF INENGAGEMENT WITH SAID SHOULDER WITH ONE LEG OF THE RETAINING MEANS BEINGIN SUBSTANTIAL COEXTENSIVE CONTACT WITH SAID FIRST INNER FACE PORTIONAND WITH THE OTHER LEG OF SAID RETAINING MEANS CONSISTING OF A PLURALITYOF INDIVIDUAL SPRING FINGERS, SAID SPRING FINGERS NORMALLY YIELDABLYENGAGING FIXED MEANS ADJACENT THE INNER CONFINES OF SAID ANNULAR SPACEAND BEING ARRANGED IN RESPECTIVE SLIDE RECEIVING SPACES FOR RESILIENTENGAGEMENT WITH THE EDGES OF SLIDES RECEIVED THEREIN.